Ready to take your BMW N20 turbo to the next level? How about up to
50hp to the wheels (65hp crank) on a completely stock car or up to
100hp to the wheels (120hp crank) on a fully modified car? The JB4
features a simple plug and play installation harness for easy
installation and includes many features not found on any other tune.
Including the ability to enable/disable the tuning from the drivers
seat, gear dependent boost control to help with traction, E85
compatibility, built in diagnostic code reading/deleting, expanded
engine safety systems, free firmware updates, in dash boost gauge, the
ability to control the exhaust flapper using your BC button, and much
more.

The JB4 does not require any additional modifications or previous
stages. Simply install the JB4 as your first and only modification and
enjoy an entirely new fast and smooth racing experience. For more
advanced enthusiasts the BMS DATA or JB4 Mobile cable allows you to
connect a laptop or smart phone for additional gauges, data logging,
and free firmware updates as we add new features and maps.

The JB4 is a fully plug and play device that installs and removes in
minutes at home without special tools and unlike flash maps that
permanently write over your DME with the JB4 your DME is never aware
it's running more than the factory power levels. And when you're ready
to change things up the JB4 is not VIN locked and can be moved to your
next vehicle or resold.